Spam training question

I was wondering, for whatever process goes through the spam email account each night, how many emails does it use each night for training?

For example, my spam training account gets a pretty fair number of mails put into it daily by users. But if I look in the account right now, it's still got some mails in it dated Dec. 1st and 2nd. There are currently about 300 messages in the spam training inbox. Half from today, maybe 75 from the 1st, and 75 from the 2nd.

There's a zmtrainsa.log (or thereabouts) that, if I recall correctly, records the number of messages learned.

As you've seen, the nightly purge job doesn't empty the spam inbox, just messages more than N days old. Feeding them to zmtrainsa again doesn't do any harm because the bayes database itself records message-ids previously seen.

IMO it would not be a bad idea to run zmtrainsa more frequently, without the --sync argument if you're concerned about load.